Author_Institution :
Lockheed Martin Co, Syracuse, NY, USA
Abstract :
In the search for a better rotating radar, a self-supporting array that rolls like a wheel can improve mechanical reliability and return higher-definition target resolution. The Rolling Radar concept evolved from the need to design and build a large rotating 3D radar as an alternative to multifaceted fixed radar installations, or large, expensive rotating radar systems. However, the physical act of rotating massive structures weighing many tons introduces a host of load bearing and other mechanical reliability problems. An alternative design needed to be conceptualized. The new concept places the radar array inside a large wheel attached to an axle. A smaller wheel affixed to the axle´s other end provides support when both wheels simultaneously roll along electrified concentric rails in order to scan 360 degrees. The array wheel propels itself via a simple gravity drive consisting of a magnetic carriage that rides an electromagnetic rail around the inside circumference of the large array wheel. Displacement of its own weight causes the wheel (and the entire axle) to roll around the railed track with no visible external means of motion. The Rolling Radar achieves its initial objective - to improve mechanical reliability - because the array wheel is self-supporting, which eliminates the need for a large support structure and bearing. There is also no need for traditional electrical slip rings, rotating fluid couplers, motors or gearboxes. With fewer moving parts (compared with conventional rotating radars), reliability is increased and life cycle costs are reduced. Another important benefit is the Rolling Radar´s electronic look back capability, and the ability to achieve higher spatial resolution than standard 3D radar. This occurs because the act of rolling about its axis and simultaneously rotating about a circumference sweeps an area larger than the array´s physical aperture. The effect is similar to spotlight-mode synthetic aperture radar (SAR), a technique commonly used to produce high-resolution radar maps. The Rolling Radar concept was initially developed to address reliability, life cycle cost, and weight. Although still in the concept development phase, the Rolling Radar shows great promise of increasing functionality while improving resolution and- reliability, and in its simplicity of design. Both the reliability and performance gains are in the process of being evaluated.
Keywords :
axles; radar equipment; reliability; wheels; Rolling Radar; axles; high-resolution radar maps; machine components; mechanical reliability; radar arrays; radar equipment; rotating 3D radar; wheels; Axles; Costs; Couplers; Electromagnetic launching; Gravity; Radar tracking; Rails; Railway electrification; Synthetic aperture radar; Wheels;